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Hi there,

my first post here :) Just want to share this build log of my first DIY quadcopter frame in carbon fiber.

Setup

- APM with GPS and Magnetometer
- 25cm Arms
- 54cm from Motor to Motor
- 18Amp HobbyWing ESC
- 750kv Motors
- 10x4.5 Props
- Turnigy nanotech 2200mha 25-50c

Extras

- HobbyKing camera with mount
- Fatshark 5.8Ghz 100mw video transmiter

Weight

- 640gr only the frame, motors and escs
- 980gr Total with the Video transmitter (not in the pictures)

Is this a good weight for this frame size and config?

About the build

I used CF 1.5mm sheet and CF tubes with 13mm diameter, to mount the motors i drilled the holes directly in the CF tube and used some plastic prop adapters to reduce vibrations. I also used some thin double side foam between the arms and top plate this way the arms will not be in direct contact with the CF plate, don't know if it helps or not. To hold the APM board the the frame i used the same double sided foam, i used 2 pieces on top of each other to give it a bit more height.

I intend to use this frame at first for some FPV, i used 8mm CF square tubes to make a camera mount, it looks pretty cool :)

I could save some grams in the wiring, but in this first step i decided to keep the wires in its original length for later changes, right now its a mess of wires between the 2 main center plates.  

Some things i noticed after the build and 2 short test flights:

I thought that it was a good idea to drill the holes in the CF tubes and mount motors directly on it, actually the tubes can handle the screws even very tighten, they didn't crack, but its hard to get perfect hole alignment without proper tools. I used an aluminum profile 15x15mm, inside diameter was 13mm exactly the outer diameter of the CF tubes, i easily drilled the holes in the aluminum profile to serve as guide and inserted the CF tubes inside. It worked pretty well, but the inclination was not so good, it's hardly noticed but motors have some minimum inclination.

I'm afraid this inclination error will affect the stability, anyone has something to say about this? I'm thinking in changing the arms to aluminum square profiles or get some mounts like Heli tail booms, it would be easy to adjust inclination.

I didn't tune PID's yet, so first flights were a bit unstable, also i wonder if having the plates stacks too high can affect the stability as well.

Also the arms look nice when short close to the motors, but will be a problem if it crashes, and i'm sure it will :(

Here are some pics of the build, Cheers!

I work out of the Loughborough University Centre for Autonomous Systems (LUCAS), and have recently discovered the Ardupilot Mega. We are now constructing a number of vehicles with Ardupilot Mega, using it as a low level control system. Our fleet will include Flying Wings, Wot 4's, and Trex 450's. We will use these to conduct research, which will range from, UAS forced landing, UAS collaboration, autonomous soaring, to collision avoidance.

This post is the first in a line of posts detailing our ArduCopters setup, testing, and eventually non-destructive (i hope) flight tests on a TRex 450. We have had out TRex 450 helicopter for quite some time, and have some rather talented pilots in out lab, but getting it flying outdoor autonomously has been an aim of ours for quite some time now. We have had TRex 250 helicopters flying autonomously using Simulink, and a Vicon camera system for some time now, but the next logical step to to go outdoors.

We have used a TRex 450 Pro so it is a bit nicer, and more powerful than the stock one. we have attached a small training undercarriage on it,in an attempt to protect Ardupilot as much as possible (mostly from my questionable flying skills).

Reading about, many people have made there own undercarriage for their Heli some of them a very nice indeed, but for the prototype it was decided that using foam and lots of zip ties it was attached to the underside of the heli. This is a really quick solution and the foam had the effect of isolating the IMU from many of the multitude of vibrations off the heli. It also protects the pressure sensor from the rotorwash. the DIP switch, USB port CLI switch, and all other outputs are still assessable. Rotary wing craft are extremely sensitive to the mounting of this autopilot system, it needs to be rigidly attached, and perfectly orthogonal to the airframe. This is because Adrupilot Mega for traditional helis does not seem to save the biases on the accelerometers on startup, which is useful but means that if it is mounted at just a few degrees off then in stabilise mode the helicopter will tend to drift off.

The magnetometer was mounted as far from the electronics as possible, so to not be affected by any errant magnetic fields from the high current wires or motor. the mag was placed on the tail boom, and a ribbon cable was ran down the struts to Ardupilot. We found a really nice way of mounting the GPS, using a small bit of aluminum bending it and drilling 2 holes, it can be screwed directly on to the airframe. Remove the screws that fix the tail boom mount to the airframe and put the screws though the aluminum and re screw on to the airframe. This way the GPS mounted on it aiming vertically up. As the GPS will be directly under the rotor disk in flight it might cause signal problems, but i doubt it. Will have to get back to you guys on that one.

Found out that there is no manual mode on Arducopter, as you have to send non ECCPM mixed signals from the transmitter. Arducopter does all the mixing for you, this makes me slightly concerned, as if all hell breaks lose I can not simply hit manual, and recover it myself. I guess this is just a matter of building confidence in the system. It did surprise me as my first experience with Ardupilot was with a flying wing which had elevon mixing, but you could send it mixed signals from the transmitter, Ardupilot would demix them to give pitch and roll commands to the fly-by-wire system, while still meaning you had the option to go to manual with the transmitters mixed signal.

Arducopter performs hight hold using the blade pitch only and does not control throttle at all. This is a problem as the pilot will have to control throttle to maintain blade speed, and I don't think anyone would be fast enough to do that especially as we plan to do some aggressive flight profiles in the future. Of course one option is to install a governor, but this is another added expense, and as we plan to get a lot more of these in the future it could soon add up. a solution could be to add the same throttle curve that you use on you transmitter to the code, this will control throttle based on a given pitch angle. This is a form of open loop control and it does work well, but to get it to maintain the optimum blade speed no matter the flight conditions, closed loop throttle control will need to coded. Using a blade speed sensor attached to one of Ardupilots ADCs would do it. In the simple hover condition this should not be a problem and as we don't plan to do anything that crazy for a while the current system will be more than addiquite.

Plan to do some simple familiarisation flights in stablise mode next, to gain some confidence in the system and try to get some good roll, and pitch gains. although the stock gains are for the TRex 450, we have to pro so they might be different, we will see.

I must stress that this is a prototype setup, as i am sure you can see our wiring "solution" is not ideal, this is to familiarise ourselves with ArduCopter. Our intial aim is to try and get as much out of Arducopter as we can with APM mission planner, and without having to change any code.

Hackaday brings news of a cool and easy way to visualize your PCBs, which is a weak point in Eagle:

"It's a software package called EagleUp that will import your Eagle CAD PCB designs into Google SketchUp. It bridges the gap between the two using the open source image processing software ImageMagick.

As you can see above, you’ll end up with a beautifully rendered 3D model of your hardware. This is a wonderful way to make sure that your enclosure designs are going to work without needing to wait for the PCBs to arrive from the fab house. It is available for Windows, OSX and Linux (although the last time we tried to run Sketchup under Wine nothing good came of it — perhaps it’s time to try again).

In [Karl's] case, he’s working on an Arduino compatible board based around the Xmega. He mentions that EagleUp is a great way to get an idea of how component placement will end up, and to see if the silk screen layer is going to turn out well or not. Here’s a link to one of his test designs."

​One of the criticisms of the Pigeon Post system I've heard multiple times is the problem of rain and other adverse weather will have on the electronic systems and on the Smart Cases.  

Now I'm not an materials expert or an electrical engineer but looking at this product demo video, I think I might have just found a solution.*  Ladies and Gentlemen, I give you NeverWet:

One question I have about this super-hydrophobic wonder spray is how easy is it to remove?  Is there a anti-superhydrophobic cleaning solution?  

So who will be the first to use this stuff on their UAV and test it out in the rain?

* Yes I know this doesn't solve the wind problem but I'll get to that another time.

Originally posted over on the Pigeon Post Blog: http://pigeonpostco.squarespace.com/blog/2011/11/16/like-water-off-a-ducks-or-pigeons-back.html

NASA captures the earth at night

http://eol.jsc.nasa.gov/Videos/CrewEarthObservationsVideos/

Hi there! Finally you can pre-order the ArduIMU V3 here.. You can find more info abut it in my last post here. 

The final version of the board for full production is here, I'm expecting to start shipping them this Friday or Monday. 

We are still working on documentation and giving the final cosmetic touches to the example code to have it ready before you have one in your hands and at the same time we are shipping samples to developers to do a full DCM integration.

From now on our new color will purple! All our new products will feature a Lilypad style look! 

(Note: this is a stand-alone IMU, and is not designed to be a replacement for the "Oilpan" IMU shield of ArduPilot Mega.)

Arduino 023 is now available here. It looks like it's just a maintenance release before the big 1.0 release

Changes:

* Added .inf files for R3 boards. 

* Updated to optiboot 4.4. 

* Included combined firmwares for ATmega16U2.

The Loughborough University Centre for Autonomous Systems (LUCAS) have spent a number of years working with an indoor rotary wing UAV test environment with little progress on outdoor testing. In recent weeks we've strapped an ArduPilot Mega to an old flying wing and have been very pleased with the results, so much so that we're now building up a dedicated Arduplane, the ArduWot.

The airframe is a Wot 4 Foam-E which comes ARTF, and when they say it's ready to go in 30 minutes they're not lying. All servos come pre-installed as does the motor and ESC. Tail surfaces slide into place and are retained by a single bolt. Wheels are pre-attatched to the legs which screw to the fuselage in seconds. The longest single task was changing the battery connector on the ESC for our preferred EC3.

The battery sits in a bay underneath the front fuselage (little blue hatch in photo below), leaving the centre fuselage pretty empty.

Our receiver is overkill for such a simple aircraft, so in reality there's more space than might first appear. The plan is to remove the foam block between the receiver and the servos and fit the APM here.

Some initial test flights today (without APM installed) showed the Wot 4 to be very easy to fly but also highly maneuverable. Most importantly for us is that it flies around nice and slowly (unlike the flying wings!) which lets us maximise the use of our relatively small test area. Tomorrow we shall be installing APM and doing plenty of test flights.

We are planning to build up a fleet of Arduplanes and Arducopters to conduct research activities such as collaboration, collision avoidance, target tracking, etc... I will keep this blog up to date with the latest developments!

People tend to assume that UAVs will be used by the police to keep watch on us, but as this video, taken by a RoboKopter of riots in Warsaw, shows, they can equally be used by citizens to keep tabs on the police. No need to wait for the local news to send a helicopter to get the aerial scene of a demonstration, just Do It Yourself!

Via Kottke

If you've used the Arduino enough to understand its shortcomings, or perhaps even dared to mention them alloud, be cheered, the gods have heard your prayers - and yes Omilex has been making devboards and breakouts long enough to be a god. This new Arduino Clone from Omilex addresses (almost) all of the complaints raised here and at Hackaday etc.. of the Arduino: with a host of pretty clever, if not always novel solutions. I'll count down the top 10 complaints again with fixes provided by the engineers at Omilex. 

#10. Accidental resets - Re-introduce the Atmel recommended noise suppression - check.

#9. Analog sucks - Separate regulator for Analog, optional Vref for even more precision - check.

#8. Shields cover reset switch - move switch - check.

#7. Shields short out on USB connector - use mini usb check.

#6. Pin layout is Random - new set of .1 centered pins - check.

#5. Frequency dependencies - provide replaceable crystal - check

#5. Linear regulators suck - use proper regulator - check.

#4. Pin assignment is Random - group power and signal together in Uext connector for GPS, ZIGBEE, I2C, etc...

#3. Power wire in a portable world - add lithium charger and auto switching - check.

#2. 5v in a 3v volt world - provide 5v/3.3v switch.

#1. Battery life sucks - lose the firestarter and add real ULP Voltage regulators - check.

And this is the short list, add real time clock support, 4 mounting holes, and Industrial temperature components and the Olimexino is far and away the highest quality Arduino Board ever produced for $29 on Mouser.

What do you think about that? It is similar in concept with the helicopters from the movie Avatar, it uses differential thrust and independent tilt for each rotor. It doesn't look very stable but this looks like a very primitive prototype. Maybe it has the potential for something quite cool.

Now this is a new meaning for "get high" (...and fast).

"Qu8k" from Derek Deville's is an terrific rocket project. On Setember 30,2011 the Qu8k was launched from the Black Rock Desert in Nevada.

The platform includes: 2 timers, 4 GPS, 1 Accelerometer and 1 Cosmic Ray Detector.

All the captured HD 1080p images you'll see are really cool. It was filmed by three cameras aboard (2 GoPro and 1 FlipHD) and many others on the ground, attached to the launch tower, etc.

From the construction to the power at the launch time, all is very exciting.

Here goes the link: https://www.youtube.com/watch?v=rvDqoxMUroA

Enjoy it!

Hi,

 I built a  V shaped with 12 motor and coaxial prop 
I know that the V shape is patented by Asctec.
This is a test only for learning purpose.

Is based on Coridium ARMmite pro controller.

Motor: keda 50-20s with 8x4.5 prop

Gyro ITG3200, Acc BMA180, Lipo 5000 mAh

Good 30-min program with a set of interviews with people doing everything from bird monitoring to search and rescue in Colorado. Aircraft range from a 4ft Cessna model to a Draganflier. Includes some interesting observations on crazy regulatory barriers (calling a control tower many miles away to say that you'll be operating a model heli at 10ft in the woods) and privacy laws (they need a search warrant to fly over someone's back yard).

Here's the description:

"There’s a lot of technology we depend on that came from the military. The Internet’s probably the best known. GPS, too. And satellites. The next big technology transfer could be unmanned aircraft. Planes with no pilots inside. The military flies a lot of these so-called drones in Iraq and Afghanistan. But in the United States, civilians aren’t really allowed to fly unmanned planes. There are a few exceptions, two of them here in Colorado. In Mesa County, a helicopter the size of a microwave does detective work. And the San Luis Valley, a small plane counts wildlife. More on that shortly. First, a chat with CPR’s Zachary Barr. He just got back from the first conference of Coloradans who build and design unmanned vehicles for air, certainly, but land and sea, too. Zac reports that people in this industry believe it has a bright future, but it would be even more promising if government regulators would loosen regulations."

After getting the board from 3D Robotics, motor from RCtigermotor, ESCs from HK... some stuff from Flytron as well.. I started to build:

1. Materials

Frames: DIY CNC Fiber Carbon + Alu 10x15mm x 340mm long

assembled motor to the arms:

with ESCs:

with landing, the FC one is too weak and I could not use it. I used landing of Heli500

with ArduCopter control

The other view:

foldable:

Well it is November again. Which to some of us means a chance of snow. I was sitting around yesterday, looking for something to do. Well I found it. Thinking back a year ago, I remembered, how much my back hurt, from shoveling my walks.

Several years ago I had an idea, What if there was a way to make a machine shovel my walks for me, it could be controlled from my computer, and I watch what was going on from my screen. Well at that time, things like ArduRover simply didn't exist.

Now things do exist that could make this thing a reality. If a CAN (controller area network) system could be interfaced with ArduRover for the control stuff, hydraulics, heavy electric motor controls, and so on, there could be one of these included in everyone's arsenal for countering winter's assault. Well probably not everyone's, but for those fortunate enough to have a six figure income could have one. Well that leaves me out.

This was drawn with SketchUp, animated with SketchyPhysics. I used a video capture program to make the video, so the quality isn't top notch, but good enough for viewers to get the general idea.

Enjoy, hope it gets those gears turning.

The DJI Wookong multi rotor M was put through a set of tests this afternoon, the first was normal flight, we then moved to position hold and changed the altitude, the DJI proved to be extremely stable in flight and held a very solid position in the sky, when the altitude change was done in GPS position hold it didn't drift, it maintained its position, the Return To Launch was the final test we did, it saw the copter back to home with only a few meters from where it took off! The DJI will rise to 20 meters if below 20 meters or stay at the same height if above for the RTL, when above the take off position it lowers to the ground and kills the engines!

This to date has to be the best multi rotor controller I have seen in action!! I know ACM will catch up soon :)

Regards

Martin

www.buildyourowndrone.co.uk

A V-tail hotliner integrated with autopilot.
Endurance 30min because of small fuselage capacity,
cruise speed 50km/h. Shown loiters on small altitude since
at typical cruise altitude of 200m it is almost impossible to track a flying object on a clear sky.

Dear Friend,

I'm happy to present my last creation :

Original blog post : http://www.virtualrobotix.com/profiles/blogs/virtualrobotix-telemetry-board

This telemetry board use AVR 644P as micro controller the code is developed in C++ using some Arduino library. Great Thanks to Sandro Benigno for OSD routine , and other people that are working on OSD code and other opensource library that I use in my new product.

The Board

• ATmega644P 20 Mhz with Arduino bootloader
• MAX7456 monochrome on-screen display
• Serial that support Jeti RTX telemetry data link.
• I2C that support Aurora9 RTX telemetry channel (work in progress).
• GPRS Module for long range comunication that using tcp/ip channel . (option)
• Serial port that support Mavlink protocol for interconnect board that use that kind of protocol as Arducopter(32) , Arduplane ecc ecc.
• Is possible to customize the protocol for interrconnection with Mikrokopter , Multiwii or Aeroquad platform and also other platform that you like if you have documentation of comunication protocol.

Is possible to recive the telemetry as overlay of video during the flight or on your prefered Jeti or Aurora radio. Other interface will be implement also on futaba and graupner radio.

All the data available on the quad is visible by telemetry option , we are also working on realtime setting of parameter during the fly directly for example jeti box.

As option is possible to mount GPRS module so you can interconnect your ground station by gprs so in case of lost your quad you can try to found it using long range telemetry module.

The price will be define in the next week and depend of option that you want.

Any kind of suggestions is welcome.

Best

Roberto

I did some wing loading testing this week in an effort to determine 1.) the affects of adding more weight to flight and 2.) determine the safe maximum wing loading / thrust to weight ratio that my scratch built airplane could handle.

This learning will help me as I seek to build a FPV/Drone airplane next year.

Detailed Results:

(Easy Star wing's surface area is roughly 368 square inches. Wing loading (wl) is reported in grams per inch)

Standard Weight: 747g, wl= 2.03 (Great Takeoff, Half throttle needed cruise, Great climb rate, Easy Landing)

2oz & case added: 813g, wl = 2.21 (Unchanged performance)

4oz added: 868g, wl = 2.36 (Slightly affected climb rate)

6oz added: 924g, wl = 2.51 (Cruise and climb rate affected, landing and take off faster)

8oz added: 980g, wl = 2.66 (Cruise and climb rate affected, landing and take off faster, controls were less responsive)

10oz added: 1,037g, wl = 2.82 (Almost maxium weight for this power/wing set up. Full throttle needed)

12oz added: 1,092g, wl = 2.97 (Maximum weight. Fast take off, fast landing, full attention needed at all times to not crash)